Improvement in balanced slide-valves



R. TREMAlN.

Improvement in Balanced SHde-Valves.

Patented May 7, T872.

Inventor:

Witnesses' AM PHD/ULIIHUGRAFH/C 50 MY. (OSBORIVES PEOCESS.)

UNITED STATES PATENT OFFICE,

RICHARD TREMAIN, OF SYRACUSE, NElV YORK.

IMPROVEMENT IN BALANCED SLIDE-VALVES.

Specification forming part of Letters Patent No. 126,427, dated May 7,1872.

To all to whom these presents shall come:

Be it known that I, RICHARD TREMAIN, of the city of Syracuse, in thecounty of Onondaga and State of New York, have invented a new andImproved Balance Slide-Valve;

The steam may be fed at any convenient point.

into the steam-chest D. Upon the top of the steam-chest I place acylinder, E, into which is fitted the piston P, having a connecting-rod,R, with one end attached to the top of the Valve V in any ordinarymanner, and the other end to the under side of the piston P by aknuckle-joint, W, substantially as shown in the drawing. The piston P isfitted and packed in any ordinaryway but it is better to be in bellform, substantially as shown in the drawing. The object of the cylinderE and piston P is to create an upward pressure of steam upon the pistonP nearly equal to the downward pressure upon the valve V, and therebyreduce the friction of the valve. The piston P has a cap, M, fitted onthe top of the piston, and properly fastened thereto, into which capanother connecting-rod, G, is firmly inserted and passes through thestuffing-box H, which is inserted into the cover F of the cylinder E,substantially as shown in the drawing, and connects with the smallpiston N,

which works in the small cylinder 0, which rests upon and is fastened tothe cover F of the large cylinder E. The object of the small cylinder 0and piston N is to lift the valve V from the valve-seat A, when theengine is running, without using steam in the working-cylinder of theengine; and this is effected by connecting in any convenient manner by apipe, X, with the boiler the steam-chamber of the small cylinder 0. T isa pipe in the cover of the cylinder E, to prevent a vacuum above thepiston P and let off any steam that may accumulate there by leakage. Yis a cock to let off the condensed steam or water from the smallcylinder 0.

By making the piston P in bell-shaped form I gain the followingadvantages: First, I get a longer bearing on the sides to preventrocking second, it afl'ords a longer connectingrod, causing the pistonto work more vertically and with less travel; it obviates the difficultyand friction of drawing at a sharp angle, thereby cutting the cylinder.

What I claim as my invention, and desire to secure by Letters Patent,is-- 1. The small cylinder 0 and piston N, when connected by the rod Gwith the piston P, for the purpose of lifting the valve V, substantiallyin the manner described.

2. The combination of the small cylinder 0 and piston N with thecylinder E provided with bell-mouthed piston P, rod R, and attached tovalve V, substantially as and for the purpose set forth.

RICHARD TREMAIN.

Witnesses:

N. B. SMITH, G. W. SMITH.

